Abstract <p>Potato (<i>Solanum tuberosum</i> L.) is a crop with high potential productivity and is one of the main sources of food for humanity. However, the relationship between key physiological processes associated with yield remains poorly understood. The study aims to assess the relationship between physiological and biochemical processes in leaves and tubers and their impact on growth and yield formation. The morphology and rate of increase in aboveground mass is a significant factor in the formation of tubers and the yield as a whole. The increase in aboveground mass positively correlated with the accumulation of chlorophyll a (<i>r</i> = 0.57, <i>P</i> &lt; 0.05) and carotenoids (<i>r</i> = 0.64, <i>P</i> &lt; 0.05), tuber weight with proline content (<i>r</i> = –0.62, <i>P</i> &lt; 0.05) in leaves, and the amount of dry matter and starch in the tuber with the content of fatty acids. The dynamics of changes of the amount of pigments, carbohydrates, antioxidants, membrane lipids and proteins during tuber formation differs in plant groups with different yield indices. We suggested that the efficiency of sucrose transport is important not only for starch accumulation in tubers, but also for the redistribution of carbon flows between metabolic pathways of carbon utilization, both in leaves and tubers. Thus physiological and biochemical processes in the leaves of potato plants and tubers have a direct impact on the quantity and quality of the crop. The revealed dynamics of these interactions promotes better understanding of the integration of physiological processes for targeted impact on the accumulation of the crop and its quality of such an economically important crop as potatoes.</p>